JP3935302B2

JP3935302B2 - Bearing protection structure

Info

Publication number: JP3935302B2
Application number: JP2000058135A
Authority: JP
Inventors: 彰浩北村
Original assignee: Kitamura Machinery Co Ltd
Current assignee: Kitamura Machinery Co Ltd
Priority date: 2000-03-03
Filing date: 2000-03-03
Publication date: 2007-06-20
Anticipated expiration: 2020-03-03
Also published as: JP2001246525A

Description

【０００１】
【発明の属する技術分野】
本発明は、軸受ハウジングの中に軸受を備え、軸受で主軸を回転支持する構造における軸受保護構造に関する。
【０００２】
【従来の技術】
最近の工作機械においては、高速化が著しく進んで高速加工技術が確立されつつある。そして、刃物の進歩とともに主軸の回転の高速化やＸ、Ｙ、Ｚ軸の各軸の送りの高速化が進んだ。主軸の回転の高速化と、Ｘ、Ｙ、Ｚ軸の各軸の送りの高速化は、軸受の高速回転を伴う。ここで、例えば、プログラムミス等により、主軸が回転中にワークと衝突した場合、機械の主要部で回転を支えている主軸の軸受が回転中に衝撃力を直接受ける。また、加工中に急激な負荷や荷重等の力が主軸にかかった場合、加工中に主軸の軸受が急激な負荷や荷重等の力を直接受ける。これらの衝撃力や急激な負荷が軸受にかかると、主軸頭は、主軸の軸受が破壊する等の大きなダメージを受けていた。主軸の軸受が損傷すると、主軸アセンブリとして軸受ハウジングと共に主軸頭一式を交換する必要があった。このため、工作機械の修理、復旧のため、工作機械を長時間停止させなければならなかった。更に、主軸頭の交換や取替の他に、工作機械停止のため作業ができなかったことによる費用負担が莫大になる等、工場側に及ぼす損失が大きかった。
【０００３】
上述のように、従来の主軸支持構造においては、軸受にかかる衝撃力や急激な負荷を吸収し調整する事に対応していなかった。
【０００４】
【発明が解決しようとする課題】
本発明は、軸受が急激な荷重や衝撃等の力を受けても、軸受が受けたそのような荷重や衝撃等の力を吸収する、いわばショックアブソーバーの役目を果たす緩衝手段を、例えば、軸受と軸受ハウジングの間に組入れ、主軸や軸受を保護することを目的とする。
【０００５】
【課題を解決するための手段】
本発明による好適な解決手段は、請求項１に記載の軸受保持構造である。
【０００６】
【発明の実施の形態】
本発明は、軸受ハウジングの中に軸受を備え、軸受で主軸を回転支持する構造における軸受保護構造に関する。
【０００７】
本発明の典型例においては、軸受ハウジングの中に軸受を備え、軸受で主軸を回転支持し、軸受ハウジングの中で軸受に緩衝手段を接触させ、軸受が主軸の軸心方向に所定値以上の力を受けると、軸受が受けた力を複数の緩衝手段が吸収する。
【０００８】
本発明の別の実施例においては、軸受ハウジングの中で複数の軸受に複数の皿バネを接触させ、複数の軸受が主軸の軸心方向に所定値以上の力を受けると、複数の軸受が受けた力を複数の皿バネが吸収する。
【０００９】
上述のように構成することにより、複数の軸受は、所定値以上の力を受けても、破壊されずに保護される。例えば、従来は、主軸に対して定格荷重Ｆｋｇ×１．２すなわち定格荷重Ｆよりも２０％増加した荷重を設計値としていたのに対し、本発明によれば、複数の緩衝手段（皿バネ）を取り付けると、定格荷重Ｆ×１．５の荷重を設計値とすることができる。つまり、設計値を３０％増加させることが可能となる。
【００１０】
【実施例】
図１は、本発明の好適な実施例による軸受保護構造の概略図である。
【００１１】
工作機械は、コラム２２と、ベース２４と、サドル２６と、テーブル２８と、主軸頭３０を有する。コラム２２は、ベース２４上に配置されている。コラム２２の中には、主軸頭３０が配置されている。主軸頭３０は、モータ（図示せず）を駆動することによりＺ方向に移動する。サドル２６は、ベッド２４上に配置されている。サドル２６は、モータ３２を駆動することにより、Ｙ方向に移動する。サドル２６上には、テーブル２８が配置されている。テーブル２８は、モータ（図示せず）を駆動することにより、Ｘ方向に移動する。
【００１２】
図２は、図１に示される工作機械の主軸頭の一部を拡大した図である。
【００１３】
主軸頭３０（図１）は、軸受ハウジング３４と、主軸３６と、軸受３８、４０、４２、４４と、緩衝手段６０、６２を有する。軸受ハウジング３４の内周面には、軸受３８、４０、４２、４４が配置されている。軸受３８、４０、４２、４４は、主軸３６を回転支持している。軸受３８は、内輪３８ａと、外輪３８ｂと、転動体３８ｃを有する。軸受３８は、内輪３８ａと外輪３８ｂの間に転動体を介在させている。軸受４０は、内輪４０ａと、外輪４０ｂと、転動体４０ｃを有する。軸受４０は、内輪４０ａと外輪４０ｂの間に転動体４０ｃを介在させている。軸受４２は、内輪４２ａと、外輪４２ｂと、転動体４２ｃを有する。軸受４２は、内輪４２ａと外輪４２ｂの間に転動体４２ｃを介在させている。軸受４４は、内輪４４ａと、外輪４４ｂと、転動体４４ｃを有する。軸受４４は、内輪４４ａと外輪４４ｂの間に転動体４４ｃを介在させている。
【００１４】
軸受ハウジング３４の内周面には、軸受止め４８、５２、５６が配置されている。軸受止め４８は、軸受３８と軸受４０の間に配置されている。軸受止め４８は、軸受３８の外軸３８ｂと軸受４０の外輪４０ｂに接触している。軸受止め５２は、軸受４０と軸受４２の間に配置されている。軸受止め５２は、軸受４０の外輪４０ｂと軸受４２の外輪４２ｂに接触している。軸受止め５６は、軸受４２と軸受４４の間に配置されている。軸受止め５６は、軸受４２の外輪４２ｂと軸受４４の外輪４４ｂに接触している。主軸３６の外周面には、軸受止め４６、５０、５４が配置されている。軸受止め４６は、軸受３８と軸受４０の間に配置されている。軸受止め４６は、軸受３８の内輪３８ａと軸受４０の内輪４０ａに接触している。軸受止め５０は、軸受４０と軸受４２の間に配置されている。軸受止め５０は、軸受４０の内輪４０ａと軸受４２の内輪４２ａに接触している。軸受止め５４は、軸受４２と軸受４４の間に配置されている。軸受止め５４は軸受４２の内輪４２ａと軸受４４の内輪４４ａに接触している。
【００１５】
また、軸受ハウジング３４の内周面には、凸部５８が形成されている。凸部５８は、軸受ハウジング３４の内周面に沿って形成されている。さらに、軸受ハウジング３４の内周面上には、複数の緩衝手段６０、６２が軸受４４と凸部５８の間に配置されている。
【００１６】
緩衝手段６０は、受け部材６０ａと、皿バネ６０ｂ、６０ｃ、６０ｄを有する。受け部材６０ａは、皿バネ６０ｂに取り付けられている。皿バネ６０ｂは、皿バネ６０ｃに取り付けられている。皿バネ６０ｃは、皿バネ６０ｄに取り付けられている。皿バネ６０ｄは、凸部５８に取り付けられている。また、受け部材６０ａは、軸受４４の外輪４４ｂに一定圧力をかけた状態で接触して配置されている。受け部材６０ａが力を受けると、受け部材６０ａが受けた力は皿バネ６０ｂ、６０ｃ、６０ｄに伝わる。したがって、受け部材６０ａが受けた力は、皿バネ６０ｂ、６０ｃ、６０ｄにより吸収される。緩衝手段６２は、受け部材６２ａと、皿バネ６２ｂ、６２ｃ、６２ｄを有する。受け部材６２ａは、皿バネ６２ｂに取り付けられている。皿バネ６２ｂは、皿バネ６２ｃに取り付けられている。
皿バネ６２ｃは、皿バネ６２ｄに取り付けられている。皿バネ６２ｄは、凸部５８に取り付けられている。また、受け部材６２ａは、軸受４４の外輪４４ｂに一定圧力をかけた状態で接触して配置されている。受け部材６２ａが力を受けると、受け部材６２ａが受けた力は皿バネ６２ｂ、６２ｃ、６２ｄに伝わる。したがって、受け部材６２ａが受けた力は、皿バネ６２ｂ、６２ｃ、６２ｄにより吸収される。
【００１７】
例えば、プログラムミスにより、主軸３６に工具を取付けたまま加工中にワークＷと主軸３６が干渉し、主軸３６が主軸３６の軸心方向の向きＹに所定値以上の力を受けた場合、軸受３８、４０、４２、４４は、主軸３６の軸心方向の向きＹに所定値以上の力を受ける。つまり、軸受３８、４０、４２、４４は、予め機械の加工能力に基づいて計算された軸受の推力Ｆｋｇより大きな力を受ける。主軸３６が受けた所定値以上の力は、軸受３８の内輪３８ａと、軸受止め４６と、軸受４０の内輪４０ａと、軸受止め５０と、軸受４２の内輪４２ａと、軸受止め５４と、軸受４４の内輪４４ａに伝わる。軸受３８の内輪３８ａに伝わった所定値以上の力は、軸受３８の転動体３８ｃに伝わり、軸受３８の外輪３８ｂ伝わる。軸受４０の内輪４０ａに伝わった所定値以上の力は、軸受４０の転動体４０ｃに伝わり、軸受４０の外輪４０ｂ伝わる。軸受４２の内輪４２ａに伝わった所定値以上の力は、軸受４２の転動体４２ｃに伝わり、軸受４２の外輪４２ｂ伝わる。軸受４４の内輪４４ａに伝わった所定値以上の力は、軸受４４の転動体４４ｃに伝わり、軸受４４の外輪４４ｂ伝わる。軸受３８の外輪３８ｂに伝わった力は、軸受止め４８を介して軸受４０の外輪４０ｂに伝わる。軸受４０の外輪４０ｂに伝わった力は、軸受止め５２を介して軸受４２の外輪４２ｂに伝わる。軸受４２の外輪４２ｂに伝わった力は、軸受止め５６を介して軸受４４の外輪４４ｂに伝わる。このため、軸受３８は、主軸３６の軸心方向の向きＹに移動する。軸受止め４８は、主軸３６の軸心方向の向きＹに移動する。軸受４０は、主軸３６の軸心方向の向きＹに移動する。軸受止め５２は、主軸３６の軸心方向の向きＹに移動する。軸受４２は、主軸３６の軸心方向の向きＹに移動する。軸受止め５６は、主軸３６の軸心方向の向きＹに移動する。軸受４４は、主軸３６の軸心方向の向きＹに移動する。ここで、緩衝手段６０、６２は、軸受４４の外輪４４ｂに所定の圧力をかけた状態で接触している。したがって、軸受３８が受けた力は、軸受３８の内輪３８ａと、軸受３８の転動体３８ｃと、軸受３８の外輪３８ｂと、軸受止め４８と、軸受４０の外輪４０ｂと、軸受止め５２と、軸受４２の外輪４２ｂと、軸受止め５６と、軸受４４の外輪４４ｂを介して緩衝手段６０、６２に吸収される。このため、軸受３８の損傷が防止される。軸受４０が受けた力は、軸受４０の内輪４０ａと、軸受４０の転動体４０ｃと、軸受４０の外輪４０ｂと、軸受止め５２と、軸受４２の外輪４２ｂと、軸受止め５６と軸受４４の外輪４４ｂを介して緩衝手段６０、６２に吸収される。このため、軸受４０の損傷が防止される。軸受４２が受けた力は、軸受４２の内輪４２ａと、軸受４２の転動体４２ｃと、軸受４２の外輪４２ｂと、軸受止め５６と、軸受４４の外輪４４ｂを介して緩衝手段６０、６２に吸収される。このため、軸受４２の損傷が防止される。軸受４４が受けた力は、軸受４４の内輪４４ａと、軸受４４の転動体４４ｃと、軸受４４の外輪４４ｂを介して緩衝手段６０、６２に吸収される。このため、軸受４４の損傷が防止される。つまり、軸受３８、４０、４２、４４が所定値以上の力を受けると、緩衝手段６０の皿バネ６０ｂ、６０ｃ、６０ｄと、緩衝手段６２の皿バネ６２ｂ、６２ｃ、６２ｄがダンパーの役目をなし、軸受３８、４０、４２、４４を破壊することなく、受けた力を吸収して軸受３８、４０、４２、４４と主軸３６を保護する。尚、緩衝手段６０、６２は、軸受４４の外輪４４ｂに所定の圧力をかけた状態で接触しているため、主軸が回転中であっても、静止していても軸受３８、４０、４２、４４の損傷は防止される。
【００１８】
【発明の効果】
本発明によれば、軸受が主軸の軸心方向に急激な荷重や衝撃等の力を受けても、それらの荷重や衝撃等の力が複数の緩衝手段（皿バネ）により吸収されるため、軸受の損傷が防止されて軸受が保護される。
【図面の簡単な説明】
【図１】本発明の好適な実施例による軸受保護構造の概略図。
【図２】図１に示される工作機械の主軸頭の一部を拡大した図。
【符号の説明】
３４軸受ハウジング
３８、４０、４２、４４軸受
６０、６２緩衝手段
３０主軸頭
３６主軸
３８ａ、４０ａ、４２ａ、４４ａ内輪
３８ｂ、４０ｂ、４２ｂ、４４ｂ外輪
３８ｃ、４０ｃ、４２ｃ、４４ｃ転動体
６０ａ、６２ａ受け部材
６０ｂ、６０ｃ、６０ｄ、６２ｂ、６２ｃ、６２ｄ皿バネ[0001]
BACKGROUND OF THE INVENTION
The present invention is provided with a bearing in a bearing housing, to the bearing protective structure in the structure for rotatably supporting the main shaft in bearings.
[0002]
[Prior art]
In recent machine tools, the speed is remarkably advanced and high-speed machining technology is being established. With the advancement of blades, the speed of rotation of the main spindle and the speed of feeding of each axis of the X, Y, and Z axes have progressed. Increasing the rotation speed of the main shaft and increasing the feed speed of each of the X, Y, and Z axes involves high-speed rotation of the bearing. Here, for example, when the main shaft collides with the workpiece during rotation due to a program error or the like, the bearing of the main shaft that supports the rotation of the main part of the machine directly receives an impact force during the rotation. Further, when a force such as a sudden load or load is applied to the spindle during machining, the spindle bearing directly receives a force such as a sudden load or load during machining. When such an impact force or a sudden load is applied to the bearing, the spindle head suffered a large damage such as destruction of the spindle bearing. If the spindle bearing is damaged, the spindle assembly must be replaced with the bearing housing as the spindle assembly. For this reason, the machine tool had to be stopped for a long time in order to repair and restore the machine tool. Furthermore, in addition to the spindle head replacement and replacement, there was a large loss on the factory side, such as the huge burden of expenses due to the inability to work because the machine tool stopped.
[0003]
As described above, the conventional spindle support structure does not support absorbing and adjusting the impact force or a sudden load applied to the bearing.
[0004]
[Problems to be solved by the invention]
The present invention relates to a shock absorber that acts as a shock absorber so as to absorb a force such as a load or an impact received by the bearing even if the bearing receives a sudden load or an impact such as an impact. The purpose of this is to protect the main shaft and bearings.
[0005]
[Means for Solving the Problems]
A preferred solution according to the present invention is the bearing holding structure according to claim 1.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is provided with a bearing in a bearing housing, to the bearing protective structure in the structure for rotatably supporting the main shaft in bearings.
[0007]
In a typical embodiment of the present invention, comprises a bearing in a bearing housing, to rotate the support of the main shaft in bearings, is contacted with a buffer means to the bearing in the bearing housing, the bearing is a predetermined value in the axial direction of the main axis When receiving the above force, the plurality of buffer means absorb the force received by the bearing.
[0008]
In another embodiment of the present invention, contacting a plurality of disc springs in a plurality of bearings in the bearing housing, the plurality of bearing receives a force greater than a predetermined value in the axial direction of the main shaft, a plurality of bearings Multiple disc springs absorb the received force.
[0009]
By configuring as described above, the plurality of bearings are protected without being destroyed even when a force of a predetermined value or more is applied. For example, in the past, the rated load Fkg × 1.2, that is, a load increased by 20% from the rated load F was used as the design value, whereas according to the present invention, a plurality of buffer means (disc springs) are used. When is attached, a load with a rated load F × 1.5 can be set as a design value. That is, the design value can be increased by 30%.
[0010]
【Example】
FIG. 1 is a schematic view of a bearing protection structure according to a preferred embodiment of the present invention.
[0011]
The machine tool includes a column 22, a base 24, a saddle 26, a table 28, and a spindle head 30. The column 22 is disposed on the base 24. A spindle head 30 is disposed in the column 22. The spindle head 30 moves in the Z direction by driving a motor (not shown). The saddle 26 is disposed on the bed 24. The saddle 26 moves in the Y direction by driving the motor 32. A table 28 is arranged on the saddle 26. The table 28 moves in the X direction by driving a motor (not shown).
[0012]
Figure 2 is an enlarged view of a part of a spindle head of a machine tool shown in FIG.
[0013]
The spindle head 30 (FIG. 1 ) has a bearing housing 34, a spindle 36, bearings 38, 40, 42 and 44, and buffer means 60 and 62. Bearings 38, 40, 42, and 44 are disposed on the inner peripheral surface of the bearing housing 34. The bearings 38, 40, 42 and 44 support the main shaft 36 in rotation. The bearing 38 includes an inner ring 38a, an outer ring 38b, and a rolling element 38c. The bearing 38 has a rolling element interposed between the inner ring 38a and the outer ring 38b. The bearing 40 includes an inner ring 40a, an outer ring 40b, and a rolling element 40c. The bearing 40 has a rolling element 40c interposed between an inner ring 40a and an outer ring 40b. The bearing 42 includes an inner ring 42a, an outer ring 42b, and a rolling element 42c. The bearing 42 has a rolling element 42c interposed between the inner ring 42a and the outer ring 42b. The bearing 44 includes an inner ring 44a, an outer ring 44b, and a rolling element 44c. The bearing 44 has a rolling element 44c interposed between the inner ring 44a and the outer ring 44b.
[0014]
Bearing stoppers 48, 52, and 56 are arranged on the inner peripheral surface of the bearing housing 34. The bearing stopper 48 is disposed between the bearing 38 and the bearing 40. The bearing stopper 48 is in contact with the outer shaft 38 b of the bearing 38 and the outer ring 40 b of the bearing 40. The bearing stopper 52 is disposed between the bearing 40 and the bearing 42. The bearing stopper 52 is in contact with the outer ring 40 b of the bearing 40 and the outer ring 42 b of the bearing 42. The bearing stopper 56 is disposed between the bearing 42 and the bearing 44. The bearing stopper 56 is in contact with the outer ring 42 b of the bearing 42 and the outer ring 44 b of the bearing 44. Bearing stops 46, 50, 54 are arranged on the outer peripheral surface of the main shaft 36. The bearing stopper 46 is disposed between the bearing 38 and the bearing 40. The bearing stopper 46 is in contact with the inner ring 38 a of the bearing 38 and the inner ring 40 a of the bearing 40. The bearing stopper 50 is disposed between the bearing 40 and the bearing 42. The bearing stopper 50 is in contact with the inner ring 40 a of the bearing 40 and the inner ring 42 a of the bearing 42. The bearing stopper 54 is disposed between the bearing 42 and the bearing 44. The bearing stopper 54 is in contact with the inner ring 42 a of the bearing 42 and the inner ring 44 a of the bearing 44.
[0015]
A convex portion 58 is formed on the inner peripheral surface of the bearing housing 34. The convex portion 58 is formed along the inner peripheral surface of the bearing housing 34. Further, on the inner peripheral surface of the bearing housing 34, a plurality of buffer means 60 and 62 are disposed between the bearing 44 and the convex portion 58.
[0016]
The buffer means 60 includes a receiving member 60a and disc springs 60b, 60c, and 60d. The receiving member 60a is attached to the disc spring 60b. The disc spring 60b is attached to the disc spring 60c. The disc spring 60c is attached to the disc spring 60d. The disc spring 60d is attached to the convex portion 58. Further, the receiving member 60a is arranged in contact with the outer ring 44b of the bearing 44 in a state where a constant pressure is applied. When the receiving member 60a receives a force, the force received by the receiving member 60a is transmitted to the disc springs 60b, 60c, and 60d. Therefore, the force received by the receiving member 60a is absorbed by the disc springs 60b, 60c, and 60d. The buffer means 62 includes a receiving member 62a and disc springs 62b, 62c, and 62d. The receiving member 62a is attached to the disc spring 62b. The disc spring 62b is attached to the disc spring 62c.
The disc spring 62c is attached to the disc spring 62d. The disc spring 62d is attached to the convex portion 58. The receiving member 62a is disposed in contact with the outer ring 44b of the bearing 44 in a state where a constant pressure is applied. When the receiving member 62a receives a force, the force received by the receiving member 62a is transmitted to the disc springs 62b, 62c, and 62d. Accordingly, the force received by the receiving member 62a is absorbed by the disc springs 62b, 62c, and 62d.
[0017]
For example, when a workpiece is attached to the main shaft 36 due to a program error and the workpiece W interferes with the main shaft 36 during machining, and the main shaft 36 receives a force greater than a predetermined value in the direction Y in the axial direction of the main shaft 36, the bearing 38, 40, 42 and 44 receive a force of a predetermined value or more in the direction Y of the main shaft 36 in the axial direction. That is, the bearings 38, 40, 42, and 44 receive a force larger than the thrust Fkg of the bearing calculated in advance based on the machining capability of the machine. The force exceeding the predetermined value received by the main shaft 36 includes an inner ring 38a of the bearing 38, a bearing stopper 46, an inner ring 40a of the bearing 40, a bearing stopper 50, an inner ring 42a of the bearing 42, a bearing stopper 54, and a bearing 44. To the inner ring 44a. A force greater than or equal to a predetermined value transmitted to the inner ring 38 a of the bearing 38 is transmitted to the rolling elements 38 c of the bearing 38 and transmitted to the outer ring 38 b of the bearing 38. A force greater than or equal to a predetermined value transmitted to the inner ring 40 a of the bearing 40 is transmitted to the rolling element 40 c of the bearing 40 and transmitted to the outer ring 40 b of the bearing 40. A force greater than or equal to a predetermined value transmitted to the inner ring 42a of the bearing 42 is transmitted to the rolling elements 42c of the bearing 42 and transmitted to the outer ring 42b of the bearing 42. A force greater than a predetermined value transmitted to the inner ring 44a of the bearing 44 is transmitted to the rolling element 44c of the bearing 44 and transmitted to the outer ring 44b of the bearing 44. The force transmitted to the outer ring 38 b of the bearing 38 is transmitted to the outer ring 40 b of the bearing 40 via the bearing stopper 48. The force transmitted to the outer ring 40 b of the bearing 40 is transmitted to the outer ring 42 b of the bearing 42 via the bearing stopper 52. The force transmitted to the outer ring 42 b of the bearing 42 is transmitted to the outer ring 44 b of the bearing 44 through the bearing stopper 56. For this reason, the bearing 38 moves in the direction Y in the axial direction of the main shaft 36. The bearing stopper 48 moves in the direction Y in the axial direction of the main shaft 36. The bearing 40 moves in the direction Y in the axial direction of the main shaft 36. The bearing stopper 52 moves in the direction Y in the axial direction of the main shaft 36. The bearing 42 moves in the direction Y in the axial direction of the main shaft 36. The bearing stopper 56 moves in the direction Y in the axial direction of the main shaft 36. The bearing 44 moves in the direction Y in the axial direction of the main shaft 36. Here, the buffer means 60 and 62 are in contact with the outer ring 44b of the bearing 44 with a predetermined pressure applied. Therefore, the force received by the bearing 38 includes the inner ring 38a of the bearing 38, the rolling element 38c of the bearing 38, the outer ring 38b of the bearing 38, the bearing stopper 48, the outer ring 40b of the bearing 40, the bearing stopper 52, and the bearing. 42 is absorbed by the buffer means 60 and 62 via the outer ring 42 b of the bearing 42, the bearing stopper 56, and the outer ring 44 b of the bearing 44. For this reason, damage to the bearing 38 is prevented. The force received by the bearing 40 includes the inner ring 40a of the bearing 40, the rolling element 40c of the bearing 40, the outer ring 40b of the bearing 40, the bearing stopper 52, the outer ring 42b of the bearing 42, the bearing stopper 56, and the outer ring of the bearing 44. It is absorbed by the buffer means 60 and 62 through 44b. For this reason, damage to the bearing 40 is prevented. The force received by the bearing 42 is absorbed by the buffer means 60 and 62 via the inner ring 42 a of the bearing 42, the rolling element 42 c of the bearing 42, the outer ring 42 b of the bearing 42, the bearing stopper 56, and the outer ring 44 b of the bearing 44. Is done. For this reason, damage to the bearing 42 is prevented. The force received by the bearing 44 is absorbed by the buffer means 60 and 62 via the inner ring 44 a of the bearing 44, the rolling element 44 c of the bearing 44, and the outer ring 44 b of the bearing 44. For this reason, damage to the bearing 44 is prevented. That is, when the bearings 38, 40, 42, 44 receive a force greater than a predetermined value, the disc springs 60b, 60c, 60d of the buffer means 60 and the disc springs 62b, 62c, 62d of the buffer means 62 serve as a damper. The bearing 38, 40, 42, 44 and the main shaft 36 are protected by absorbing the received force without destroying the bearings 38, 40, 42, 44. Since the buffer means 60 and 62 are in contact with the outer ring 44b of the bearing 44 with a predetermined pressure applied, the bearings 38, 40, 42, Damage to 44 is prevented.
[0018]
【The invention's effect】
According to the present invention, the bearing even under the force of such sudden load or impact in the axial direction of the main shaft, the force thereof, and the like load or impact is absorbed by the plurality of buffer means (disc spring) , Bearing damage is prevented and the bearing is protected.
[Brief description of the drawings]
FIG. 1 is a schematic view of a bearing protection structure according to a preferred embodiment of the present invention.
[2] a partial enlarged view of the spindle head of a machine tool shown in FIG.
[Explanation of symbols]
34 Bearing housing 38, 40, 42, 44 Bearing 60, 62 Shock absorber 30 Main shaft head 36 Main shaft 38a, 40a, 42a, 44a Inner ring 38b, 40b, 42b, 44b Outer ring 38c, 40c, 42c, 44c Rolling elements 60a, 62a Member 60b, 60c, 60d, 62b, 62c, 62d Belleville spring

Claims

軸受ハウジングの中に軸受を備え、軸受で、軸受の内輪に固定した主軸を回転支持し、軸受ハウジングに対して軸受の外輪が緩衝手段を介して所定の圧力をかけられた状態で設けられ、軸受の外輪が主軸の軸心方向に所定値以上の力を受けると、軸受の外輪が受けた力を緩衝手段によって吸収する構成にし、
軸受ハウジング（３４）の内周面には、複数の軸受（３８、４０、４２、４４）が軸心方向に並べて配置されており、それらの軸受（３８、４０、４２、４４）の内輪（３８ａ、４０ａ、４２ａ、４４ａ）および外輪（３８ｂ、４０ｂ、４２ｂ、４４ｂ）の間にそれぞれ１つずつ内輪用および外輪用の軸受止め（４６、４８、５０、５２、５４、５６）が配置されており、
軸受（３８、４０、４２、４４）の内輪（３８ａ、４０ａ、４２ａ、４４ａ）とそれらの間に配置された内輪用の軸受止め（４６、５０、５４）は、主軸に対して固定されており、軸受（３８、４０、４２、４４）の外輪（３８ｂ、４０ｂ、４２ｂ、４４ｂ）とそれらの間に配置された外輪用の軸受止め（４８、５２、５６）は、そのような軸受（３８、４０、４２、４４）の内輪（３８ａ、４０ａ、４２ａ、４４ａ）とそれらの間に配置された内輪用の軸受止め（４６、５０、５４）に対して、軸心方向に相対的に移動可能になっており、
さらに、軸受ハウジング（３４）の内周面には、凸部（５８）が形成されており、その凸部（５８）と軸受（４４）との間に第１及び第２緩衝手段（６０、６２）が配置されており、
第１緩衝手段（６０）は、第１受け部材（６０ａ）と、第１、第２及び第３皿バネ（６０ｂ、６０ｃ、６０ｄ）を有し、その第１受け部材（６０ａ）は、第１皿バネ（６０ｂ）に取り付け、その第１皿バネ（６０ｂ）は、第２皿バネ（６０ｃ）に取り付け、その第２皿バネ（６０ｃ）は、第３皿バネ（６０ｄ）に取り付け、その第３皿バネ（６０ｄ）は、凸部（５８）に取り付け、第１受け部材（６０ａ）は、軸受（４４）の外輪（４４ｂ）に一定圧力をかけた状態で接触して配置されており、第１受け部材（６０ａ）が力を受けると、その第１受け部材（６０ａ）が受けた力は、第１、第２及び第３皿バネ（６０ｂ、６０ｃ、６０ｄ）に伝わり、第１受け部材（６０ａ）が受けた力は、第１、第２及び第３皿バネ（６０ｂ、６０ｃ、６０ｄ）により吸収され、
第２緩衝手段（６２）は、第２受け部材（６２ａ）と、第１、第２及び第３皿バネ（６２ｂ、６２ｃ、６２ｄ）を有し、第２受け部材（６２ａ）は、第４皿バネ（６２ｂ）に取り付け、その第４皿バネ（６２ｂ）は、第５皿バネ（６２ｃ）に取り付け、その第５皿バネ（６２ｃ）は、第６皿バネ（６２ｄ）に取り付け、その第６皿バネ（６２ｄ）は、凸部（５８）に取り付け、第２受け部材（６２ａ）は、軸受（４４）の外輪（４４ｂ）に一定圧力をかけた状態で接触して配置されており、第２受け部材（６２ａ）が力を受けると、その第２受け部材（６２ａ）が受けた力は、第４、第５及び第６皿バネ（６２ｂ、６２ｃ、６２ｄ）に伝わり、第２受け部材（６２ａ）が受けた力は、第４、第５及び第６皿バネ（６２ｂ、６２ｃ、６２ｄ）により吸収されることを特徴とする軸受保護構造。A bearing is provided in the bearing housing, the main shaft fixed to the inner ring of the bearing is rotatably supported by the bearing, and the outer ring of the bearing is provided with a predetermined pressure applied to the bearing housing via the buffering means, When the outer ring of the bearing receives a force of a predetermined value or more in the axial direction of the main shaft, the force received by the outer ring of the bearing is absorbed by the buffer means,
A plurality of bearings (38, 40, 42, 44) are arranged in the axial direction on the inner peripheral surface of the bearing housing (34), and inner rings ( 38, 40, 42, 44) of these bearings (38, 40, 42, 44) are arranged. 38a, 40a, 42a, 44a) and outer ring (38b, 40b, 42b, 44b) , one inner ring and one outer ring bearing stop ( 46, 48, 50, 52, 54, 56) are arranged respectively. And
The inner rings (38a, 40a, 42a, 44a) of the bearings (38, 40, 42, 44) and the bearing stops (46, 50, 54) for the inner rings arranged between them are fixed to the main shaft. And the outer ring (38b, 40b, 42b, 44b) of the bearing (38, 40, 42, 44) and the bearing stop (48, 52, 56) for the outer ring arranged between them are such bearings ( 38, 40, 42, 44) relative to the inner ring (38a, 40a, 42a, 44a) and the inner ring bearing stopper (46, 50, 54) disposed between them. It ’s movable,
Further, a convex portion (58) is formed on the inner peripheral surface of the bearing housing (34), and the first and second buffering means (60, 60) are provided between the convex portion (58) and the bearing (44). 62) is arranged,
The first buffer means (60) has a first receiving member (60a) and first, second and third disc springs (60b, 60c, 60d), and the first receiving member (60a) The first disc spring (60b) is attached to the second disc spring (60c), and the second disc spring (60c) is attached to the third disc spring (60d). The third disc spring (60d) is attached to the convex portion (58), and the first receiving member (60a) is arranged in contact with the outer ring (44b) of the bearing (44) in a state where a constant pressure is applied. When the first receiving member (60a) receives a force, the force received by the first receiving member (60a) is transmitted to the first, second and third disc springs (60b, 60c, 60d), and the first The force received by the receiving member (60a) is the first, second and third disc springs (60b, 60c, 60d). Is absorbed by,
The second buffer means (62) has a second receiving member (62a) and first, second and third disc springs (62b, 62c, 62d), and the second receiving member (62a) is a fourth receiving member (62a). It is attached to the disc spring (62b), its fourth disc spring (62b) is attached to the fifth disc spring (62c), its fifth disc spring (62c) is attached to the sixth disc spring (62d), and its The 6 disc spring (62d) is attached to the convex portion (58), and the second receiving member (62a) is arranged in contact with the outer ring (44b) of the bearing (44) in a state where a constant pressure is applied, When the second receiving member (62a) receives a force, the force received by the second receiving member (62a) is transmitted to the fourth, fifth and sixth disc springs (62b, 62c, 62d), and the second receiving member. The force received by the member (62a) is applied to the fourth, fifth and sixth disc springs (62b, 62c, 62d). Bearing protective structure, characterized in that it is absorbed Ri.